/*
 * Copyright (c) 2014 pkzd/1.0, 颜文泽(robin)
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     1 Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     2 Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include	<stdio.h>
#include	<syscall.h>

void	do_cat(char *file);

int
main(int argc, char *argv[])
{
	if(argc <= 1){
		printf("Usage: cat file\n");
	}else{
		while(*++argv){
			if(argc > 2)
				printf("%s:\n", *argv);
			do_cat(*argv);
		}
	}
	exit(0);
} 

void
do_cat(char *file)
{
	int fd, cnt;
	char buf[BLKSIZ];

	if((fd = open(file, O_RDONLY, 0)) == -1){
		printf("Error: cannot open file %s\n", file);
		return;
	}
	while((cnt = read(fd, buf, BLKSIZ)) > 0)
		write(1, buf, cnt);
	close(fd);
	return;
}
